Looper mechanism for sewing machines



Dec. 19, 1933. CLAYTON 1,940,389

LOOPER MECHANISM FOR SEWING MACHINES Filed Nov. 30, 1931 3 Sheets-Sheet l I gwue/wtoz uyndrew E. Clc ryfm Dec; 19, 1933.

A. B. CLAYTON 1,940,389

LOOPER MECHANISM FOR SEWING MACHINES Filed Nov. 30, 1931 3 Sheets-Sheet 2 7 l W 24/ l 11 a 13 I Dec. 19, 1933. A. B. CLAYTON LOOPER MECHANISM FOR SEWING MACHINES Filed Nov. 30, 1931 3 Sheets-Sheet 3 Patented Dec. 19, 1933 LOOPER'" MECHANISM FOR SEWING MACHINES B; Clayton, Union, N. J., assignor to. The Singer Manufacturing Company, Elizabeth, N..J., a corporation of New Jersey Application: November 30, 19.31

' Serial No. 577,919

This invention relates towering-machines of the chain-stitch type in' which a reciprocating needle" cooperates with an endwisereciprocating looper-blade.

: object offthe invention is to providea simplifl'ed andimproved' wide-gauge multiple-looper mechanismwhichis adapted for. practical highspeedoperation.

Another object of the invention is to provide-a 19 novel looper throw-out mechanism whichis so; with the above and other objects in view, as

will hereinafter appear, the invention comprises the devices, combinations and arrangements of parts hereinafter set forth and illustrated in the accompanying. drawings of a preferred: embodiment of the invention. from which. the several features of the invention and the advantages attained thereby will be readily understood by those skilled. in the art...

Fig. 1 isa front elevation of the looper mechanism of a. sewing machine embodying the invention. Fig. 2 isa. topplan viewoi' the looper mech aniom. I Fig.3 isv a rear, elevation of the looper Fig. 4 is a section on the line 4+4, Fig. 1, with the main-shaft turned 90 from the position shown in Fig. 1 and the loopers in normal working, position below the sewing machine throat-plate. Fig. :5 is a similar view with the loopers shifted to accessible position. Fig. 6 is a section on the line 6.-6, Fig. 4. Fig. '7 is a'section on the line 7'l, Fig. 6. Fig. 8 is a plan view of the upwardly spring-pressed plate shown in Figs. 6 and 7. Fig. 9-Iis a perspective view of a section of the main looper-driving shaft. Fig. 10 is a perspective view of the shiftable bearing block for the looper-supporting spindles. Fig. 11 is a perspective view of one of the end-guiding brackets for the shiftable bearing block. Fig. 12 is a perspective view of a right angle guide-pin element of the looper-mechanism. Fig. 13 is a perspective view oi the coupled looper-carriers. Fig. 14 is'a diagrammatic view-of the looperdriving elements, and Fig. 15 is'a sectional view through the guide-pin. a H

The sewing machine is constructed with the usual bed 1, cloth-plate 2, throat-plate 3, feeddog 4-, reciprocating needle-bar5 .and main drive-,

shaft 6. The needle-bar 5xis shownascarrying: two widely spaced needles 7, 'IV as-is, customaryiin wide-gauge machines.

Cooperating with each needle 7 isv a thread; carrying looper 8 the bladeof which is disposed; transversely of the line of feed andahasitsloopq seizing and loop-shedding movements across theline of feed and its side-throw or avoiding moveq ments in the line of feed;

The loopers 8 havetheir cylindrical 8" mounted in clam'ps 9 at the upper ends of the. twin looper-carrier levers 10. having bearing spindles 11 which are journaled'in' spaced paral: lel relation in the horizontal. apertures. 12 in the, detachable bearing-block 13; the axis of each, spindle 11 being directly below or in. intersects ing relation with its respective needle. '7. The, looper-levers 10 are pivotally connectedtogether at their lower ends by the yoke. 14 having a cen-. tral bearing aperture for the pin 15. the head 16 of which is split'and is clamped to thedepende ing sleeve-element 17 of the guide-pin 18 which is received in the central guide-aperture 19 in the bearing-block 13. The guide-pin 18 and its sleeve-element 17 are normal to each other. and are preferably made in one piece.

The main drive-shaft 6 is formed with the usual inclined crank 19 which is embraced by the long sleeve-head 20 of the vibratory drive-pin 21 which is normal to the axis ofthe sleeves head 20 and works in the sleeve-element 1? and imparts rocking movements to the looper-carrier levers 10.

The axis aa of the drive-pin 21 intersects the axisbb of the inclined crank 19 at apoint 22 which is spaced from the intersection point 23 of the axis bb of the inclined crank 19 and theaxis c-c of the main-shaft 6. This spacing imparts a certain side-throw to the pin 21 and causes the yoke 14 and looper-carrier levers 10 to slide with their spindles 11,. endwise oi the latter, to impart the desired side throw comtracting strokes and the inclined crank 19 inc.

vertical plane, that the cylindrical shanks or pins 8' of the loopers 8 together with the sockets of the clamps 9 in which the pins 8 are fitted, are horizontally disposed and are parallel to the main-shaft 6. This provision permits the loopers to be bodily shifted in the clamps 9 to set their points at the correct distance from their respective needles without raising or lowering such points. Also the loopers may be rocked on their pins 8 to adjust the lateral positions of the loopers relative to their respective needles.

The detachable bearing-block 13 is mounted for up-and-down movement between the supporting guide-brackets 24 detachably secured by screws 25 to the bed 1. The inner faces of the guide-brackets 24 are formed with grooves 26 which are curved concentrically with the axis of the main-shaft 6. These grooves 26 slidably receive the similarly curvedribs 2'? on the end faces of the bearing-block 13. The bearing-block 13 has journaled therein a rock-shaft 28 bearing at one end a thumb-nut 29 and at its other end carrying a cam-shaped arm or strut 30, the end 31 of which, Fig. 6, bears upon the upwardly spring-pressed plate 32 and supports and latches the bearing-block 13 in its upper horizontal working position in engagement with the overhanging lips 24" of the guide-brackets 24. The plate 32 is hinged at 33 to the pin 34 which is secured by the screw 35in a socket in the bed 1. The

upward spring-pressure is applied to the plate 32 by springs 36,.as shown in Figs. 7 and 8.

When it is desired to shift the loopers 8 to accessible positions, the thumb-nut 29 is turned to unlatch the bearing-block l3 and permit the latter to drop from the position shown in Fig. 7' to that shown in Fig. 5, thereby turning the block 13 and the entire looper mechanism about the main-shaft axis as a center and carrying the loopers 8 forwardly of the throat-plate 3, where they may beeasily threaded. A turn of the knob 29 in a. reverse direction elevates the block 13 and latchesit in elevated position with the loopers returned to normal cooperative relation with the needles. Before throwing outthe loopers, however, the main-shaft should be turned to a point where the looper-blades are not behind the needles. Preferably, the needles should be raised above the throat-plate or the loopers should be on their retracting stroke and hence in front of the needles, as shown in-Figs.

4 and 5. v

-By providing. a bearing element or block 13 for the guide-pin 18 and looper-spindles 11, which bearing element is movable laterally of said guidepin and detachable v from the sewing machine frame 1, the assembly and disassembly of the looper-mechanism is facilitated, as it is not necessary to remove or disturb the main-shaft 6. The guide-pin 18 and its sleeve-head 17 may, moreover, be made in one piece and may be installed orremoved while the main-shaft 6 remains undisturbed in working position; a result which cannot be accomplished with the mechanismof the DeVoe Patent No. 1,100,124, and can only be accomplished in the mechanism of my prior Patent No. 1,569,912, by making the hori- 'zontal guide-pin detachable as illustrated in such patent.

The present looper-mechanism is preferably lubricated as follows: The bearing-block 13 is provided with a felt-packed cavity, 37 which receives oil from a suitable source of supply and distributes it through ducts 38-, Figsf2 and 5, to

the bearings for the spindles lland guide-pin 18.

The spindles 11 are hollow and take oil from 'ingin normal sewing tween the pin 15 and yoke 14 is lubricated. Oil'- from the groove 41 also lubricates the bearing between the sleeve-head 1'7 and the actuating pin 21.

Having thus set forth the nature of the invention, what I claim herein is:-

1. In looper mechanism for sewing machines, a main drive shaft having an inclined crank, a plurality of loopers, a plurality of looper-carrierlevers fulcrumed on axes which are parallel to one another and normal to the main shaft, a yoke pivotally connecting said looper-carrierlevers together, and an operative connection between said inclined crank and said yoke. v

2. Multiple looper mechanism for sewing machines having, a plurality of looper-carrier-levers havingspaced parallel spindles, bearings in which said spindlesare journaled for rocking and sliding movements, a yoke connecting said loopercarrier-levers below their spindles, and means for imparting endwise and lateral movements to said yoke.

3. In looper mechanism for sewing machines, a main drive shaft having an inclined crank, a plurality of loopers, a plurality of looper-carrierlevers fulcrumed on axes which are parallel to one another and normal to the main shaft, a yoke pivotally connecting said looper-carrier-levers. 1

together, an operative connection between said inclined crank and said yoke, said operative connection including a sleeve embracing said inclined crank, a pinv rigid with and normal to said sleeve, a second sleeve embracing said pin, and a secondpin rigid with and normal to said second sleeve and journaled in said yokel 4. In looper mechanism for sewing machines, a main drive shaft having an inclined crank, a' plurality of loopers, a plurality of looper-carrierlevers 'fulcrumed to rock on spaced parallel axes normal to the main drive shaft, a sleeve embracing said inclined crank, a pin normal to said sleeve, a second sleeve on said pin, a second pin carrying said second sleeve and journaled in parallelism with the axes of rocking motion of said looper-carrier-levers, a yoke. pivotally connecting said looper-carrier-levers, and a pivotal driving connection between said second sleeve and said yoke.

5. A main-shaft having an inclined crank,'a looper, a looper-carrier, a bearing in which said looper-carrier is journaled, an operative connection between said inclined crank and said loopercarrier', and means for shifting said bearing about the axis of said main-shaft as a center.

6. A main-shaft having an inclined crank, a looper, a looper-carrier, a bearing in which 'said looper-carrier is journaled, an operative connection between said inclined crank and said loop'ercarrier, said bearing being shiftable about the axis of said main-shaft as a center, and a'manually releasableelement for supporting said bearposition.

7. In a sewing machine, a throat-plate, a main drive shaft havingan inclined crank, a looper mechanism actuated by said inclined crank and including a looper having a blade performing endwise loop-seizing and loop-shedding movements below said throat-plate in opposite direc- 1 late tions, and means for turning said looper mechanism as a whole around said main drive shaft to carry the looper to an accessible position.

8. In sewing machine looper mechanism, a main-shaft having an inclined crank, a sleeve embracing said crank, a pin normal to said sleeve, a bearing member movable in an arc concentric with said main-shaft, a looper journaled in said bearing member on an axis normal to said mainshaft, and an operative connection between said pin and looper.

9. In sewing machine looper mechanism, a main-shaft having an inclined crank, a sleeve embracing said crank, a pin normal to said sleeve, a bearing member movable in an arc concentric with said main-shaft, a looper journaled in said bearing member on an axis normal to said mainshaft, an operative connection between said pin and looper, and manually releasable means for holding said bearing member fixed in sewing position.

10. In sewing machine looper mechanism, a machine-frame, a main-shaft having an inclined crank, a sleeve embracing said crank, a pin normal to said sleeve, a bearing member movable in an arc concentric with said main-shaft, a looper journaled in said bearing member on an axis normal to said main-shaft, an operative connection between said pin and looper, manually releasable means for holding said bearing member fixed in sewing position, said means including a manually operable rock-shaft journaled in said bearing member, and a latch-arm carried by said rock-shaft for cooperation with the machineframe.

11. In looper mechanism for sewing machines, a bed, a main-shaft having an inclined crank, a bearing-block mounted on and movable relative to said bed about the axis of the main-shaft as a center, a looper, a looper-lever having a spindle journaled in said bearing-block, a sleeve embracing said inclined crank, a pin normal to said sleeve, and an operative connection between said pin and looper-lever.

12. In a sewing machine, a bed, a main-shaft journaled in said bed and having an inclined crank, a sleeve embracing said crank, a pin normal to said sleeve, a second sleeve embracing said pin, a second pin normal to and in one piece with said second sleeve, a looper connected to be operated by said second sleeve, and a bearing element for said second pin mounted on said bed and shiftable relative to said bed laterally of the axis of said second pin. 7

13. The combination with a reciprocating needle, a main-shaft, a looper cooperating with said needle, a pivotally mounted oscillatory looper-carrier operatively connected with said main-shaft, and an adjustable connection between said looper and looper-carrier permitting a bodily shift of the looper on its carrier in a direction normal to the needle when the looper is at the end of its stroke ready to begin its advance to seize a needle-loop.

14. The combination with a reciprocating needle, a main-shaft, a looper cooperating with said needle, a pivotally mounted oscillatory looper-carrier operatively connected with said main-shaft, and a pin-and-socket adjustable connection between said looper and looper-carrier, the axis of said connection being normal to the needle when the looper is at the end of its stroke ready to begin its loop-seizing movement.

15. In a sewing machine, the combination with a reciprocating needle, of a looper, a movable looper-supporting bearing, and a manually releasable element supporting the weight of said bearing in sewing position.

16. In a sewing machine, the combination with a reciprocating needle, of a looper, a movable looper-supporting bearing, a manually releasable element supporting the weight of said bearing in sewing position, and a spring-pressed thrustmember engaged by said manually releasable element.

1'7. In a sewing machine, a bed, a main-shaft journaled in said bed and having an inclined crank, a sleeve embracing said crank, a pin normal to said sleeve, a second sleeve embracing said pin, a second pin normal to said second sleeve, and a bearing element for said second pin detachable from said bed and movable together with said pin in a direction transversely of said pins axis.

' ANDREW B. CLAYTON. 

